JP2009168220A - Gasket for hard disk apparatus, and manufacturing method and testing method thereof - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a gasket for a hard disk apparatus, a manufacturing method of the gasket for the hard disk apparatus and a testing method of the gasket for the hard disk apparatus capable of easily checking an application state of an adhesive after application of another material even when the another material is continuously coated on the adhesive after application of the adhesive. <P>SOLUTION: In the gasket for the hard disk apparatus to which the gasket is adhered to a cover body through the adhesive, the gasket comprises light-transmitting resin, and the adhesive includes coloring pigment mixed therein. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a gasket for a hard disk device, a method for manufacturing a gasket for a hard disk device, and a method for inspecting a gasket for a hard disk device, and more particularly, a gasket for a hard disk device capable of visually confirming an adhesive state between a gasket and a cover body. The present invention relates to a manufacturing method and an inspection method for a gasket for a hard disk device.

  In recent years, in computer hard disk devices (hereinafter sometimes referred to as “HDDs”), high performance and miniaturization have progressed, and 2.5-inch (63.5 mm) HDDs are now becoming mainstream, and 1.8 Inch (45.7 mm) and 1 inch (25.4 mm) small HDDs have also been commercialized. Such a small HDD has a complicated circuit configuration, and even a small amount of dust causes a failure. Therefore, it is generally performed to prevent dust from entering using a gasket.

  Further, as an HDD gasket used for these small HDDs, a gasket such as a wall having a narrower line width and a higher height is required. Furthermore, with the downsizing, the number of cases used for portable electronic devices is increasing, and there are cases where more precise molding is required compared to conventional PC applications and the like.

  As described above, it is extremely important to prevent dust from entering using the gasket, and a technique for bonding the gasket and the cover body using an adhesive in order to prevent dust from entering is known (see Patent Document 1). ). However, if the gasket and the cover body are bonded using an adhesive, it is difficult to confirm the presence or absence of the adhesive because the black pigment is blended as the gasket material. There has been a problem that adhesion failure may occur due to fading or missing dots.

Regarding the improvement of the adhesive, for example, Patent Document 2 discloses an adhesive containing a fluorescent agent and / or a phosphorescent agent used for a vinyl chloride resin tube or the like. Patent Documents 3 and 4 propose a technique that enables the primer application state to be confirmed by adding a fluorescent agent to the primer.
JP 2001-31470 A JP 7-34050 A Japanese Patent Laid-Open No. 11-197591 JP-A-2003-183576

  However, the techniques described in Patent Documents 2 to 4 are all for simply detecting the application state after the adhesive is applied, and after applying the adhesive, other materials are continuously formed thereon by coating. It was not intended for such a case. Therefore, even in such a case, it has been desired to realize an inspection means capable of easily confirming the application state of the adhesive.

  Therefore, the object of the present invention is to solve the above-described problems in the prior art, and after applying the adhesive, when another material is continuously formed on the adhesive, the applied state of the adhesive is subsequently changed. It is an object of the present invention to provide a hard disk device gasket, a hard disk device gasket manufacturing method, and a hard disk device gasket inspection method that can be easily confirmed.

  The present inventor has found that by using a specific resin for the gasket and blending a color pigment in the adhesive, it is possible to visually recognize the adhesion state after the gasket and the cover body are adhered. The invention has been completed.

  That is, the gasket for a hard disk device according to the present invention is a gasket for a hard disk device in which a gasket is bonded to a cover body via an adhesive. The gasket includes a light-transmitting resin as a main component, and the adhesive is colored. It is characterized by containing a pigment.

  In the gasket for a hard disk device of the present invention, the color pigment is preferably a phosphorescent pigment, and either one or both of the gasket and the adhesive is mainly composed of an ultraviolet curable resin. preferable.

  In the method of manufacturing a gasket for a hard disk device according to the present invention, in manufacturing the gasket for a hard disk device, the adhesive and the gasket are sequentially applied and formed on the cover body, and then the gasket and the adhesive are simultaneously applied. It is characterized by being cured.

  The inspection method for a gasket for a hard disk device of the present invention is an inspection method for confirming an application state of the adhesive in the gasket for the hard disk device, and after the gasket and the adhesive are cured, the gasket The application state of the adhesive is visually recognized from above.

  According to the present invention, with the above-described configuration, even when another material is continuously applied and formed thereon after application of the adhesive, the application state of the adhesive is easily confirmed thereafter. It is possible to provide a hard disk device gasket, a method for manufacturing a hard disk device gasket, and a method for inspecting a hard disk device gasket.

Hereinafter, preferred embodiments of the present invention will be described in detail.
FIG. 1 is a partial sectional view showing a preferred example of the gasket of the present invention. In the illustrated gasket 4 for a hard disk device, a gasket 1 is bonded to a cover body 3 with an adhesive 2, the gasket 1 contains a light transmissive resin as a main component, and the adhesive 2 contains a color pigment. is there.

  Since the gasket 1 contains a light-transmitting resin as a main component and the adhesive 2 contains a color pigment, the hue can be clearly distinguished from the surrounding metal plate. Easy to confirm. In addition, since the adhesive 2 contains a color pigment, the adhesive can be visually recognized more easily than a transparent adhesive or the like because light absorption / scattering is large even under a gasket material which is a semi-light transmissive material.

  The adhesive 2 used in the present invention is not particularly limited as long as it can adhere the cover body 3 and the gasket 1, and an adhesive mainly containing an ionizing radiation curable resin or a thermosetting resin. Can be mentioned. Of these, ionizing radiation curable resins, particularly those mainly composed of ultraviolet curable resins, are preferred because they can be easily cured without adversely affecting the HDD or the like.

  Although it does not specifically limit as ionizing radiation curable resin, For example, the resin composition which mixed suitably the prepolymer, oligomer, and / or monomer which have a polymerizable unsaturated bond or an epoxy group in a molecule | numerator is used. Examples of these resin systems include acrylate resins such as urethane acrylate, polyester acrylate, and epoxy acrylate, silicon resins such as siloxane, polyester, and epoxy resin. Examples of the prepolymer and oligomer include unsaturated polyesters and methacrylates. Examples of monomers include styrene monomers, acrylic esters, methacrylic esters, substituted amino alcohol esters of unsaturated acids, unsaturated carboxylic amides, and other monomers. . The above compounds are used alone or in combination of two or more, but in order to impart ordinary coating suitability to the resin composition, the prepolymer or oligomer and / or monomer are mixed in an appropriate blend. To do.

  In the present invention, among the above resins, an epoxy acrylate resin, a urethane acrylate resin, and an epoxy resin are preferable in terms of adhesiveness to the cover body, and these are used alone or in combination of two or more. Can be used. In particular, in the case where a nickel-plated and chromate-treated metal body is used as the cover body 3, an epoxy acrylate resin is used because of its high adhesiveness to these materials, for example, at a high temperature of about 85 ° C. Is preferred.

  In the present invention, the color pigment mixed in the adhesive 2 is not limited as long as the adhesion state after the gasket 1 and the cover body 3 are adhered can be visually recognized. Preferably, the phosphorescent pigment, the fluorescent pigment, or their pigments are used. It is a mixture, and a phosphorescent pigment is particularly preferable. Moreover, green and blue are preferable to red and yellow from the ease of visibility.

  Such phosphorescent pigments and fluorescent pigments are substances that absorb light when it is bright in the daytime and glow in the dark. For example, phosphorescent pigments such as zinc sulfide, barium sulfide, calcium sulfide, and calcium, barium, magnesium Fluorescent pigments mainly composed of oxides such as cadmium, sulfides, silicates, phosphates, tungstates, etc. are suitable, and mixtures thereof may also be used. In addition, when the phosphorescent pigment and fluorescent pigment are granular or massive, the granular or massive phosphorescent pigment and fluorescent pigment enter between the gasket 1 and the cover body 3 and there is a possibility that adhesion may not be performed well. It is preferable to use it.

  By blending the phosphorescent pigment and the fluorescent pigment, the visibility of the adhesive 2 can be further improved by irradiating black light in a dark place. As a result, it is possible to easily determine missing dots or fading. Further, by observing in a dark place, the influence of irregular reflection from the surrounding metal plate can be eliminated, and the visibility is further improved. Furthermore, by installing an image recognition device in a dark place, it is possible to automatically inspect the application state of the adhesive 2.

  Furthermore, in the present invention, either one or both of the gasket 1 and the adhesive 2 is preferably an ultraviolet curable resin, and by using a phosphorescent pigment and an ultraviolet curable resin in combination, the ultraviolet curable resin is irradiated with ultraviolet rays. Curing and excitation of the phosphorescent pigment can be performed simultaneously, and the adhesive 2 can be easily visually recognized without black light. In addition, by irradiating light such as ultraviolet rays at the same time, light irradiation by a separate process becomes unnecessary, and additional equipment becomes unnecessary. As a result, facilities are simplified and unnecessary cost increases can be avoided.

  In the present invention, the amount of the color pigment mixed in the adhesive 2 is not particularly limited as long as the desired effect of the present invention is obtained, but is preferably 0 with respect to 100 parts by mass of the main resin component of the adhesive 2. 0.1 to 3 parts by mass, and more preferably 0.5 to 1 part by mass. In addition, in the case of curing by ultraviolet irradiation by increasing the blending amount of the color pigment, there is a concern that the reaction initiation efficiency of the photopolymerization initiator may be significantly inhibited. There is no problem.

  Moreover, in this invention, as a viscosity at the time of application | coating to the cover body 3 of the adhesive agent 2 in which the color pigment was mixed, the range of 10-1000 mPa * s is preferable in 25 degreeC. When the pressure is 10 mPa · s or more, there is no problem such that the adhesive 2 flows out before curing, and there is no problem, so that the dimensional stability is good. On the other hand, applicability | paintability is favorable in it being 1000 mPa * s or less. From the above viewpoint, the viscosity of the adhesive 2 at 25 ° C. is more preferably in the range of 100 to 500 mPa · s.

  Furthermore, in the present invention, it is important to apply the adhesive 2 to the cover body 3 in accordance with the shape of the gasket 1. As a result, the gasket 1 is securely bonded to the cover body 3, and since the protruding portion of the adhesive 2 is small, gas generating components are further suppressed, and adverse effects on the HDD can be suppressed. A method for applying the adhesive 2 to the cover body 3 is not particularly limited, and a stamp transfer, printing method, or the like can be used. In the present invention, the adhesive 2 is particularly preferably a three-dimensional automatic application control device. It is preferable to apply using. The three-dimensional automatic application control device is used to apply the gasket 1 to the cover body 3 as will be described later. By controlling the three-dimensional automatic application control device with the same program, the shape of the gasket 1 is applied to the cover body 3. Accordingly, it is possible to apply the adhesive 2 precisely.

  In the present invention, after the adhesive 2 is applied, the adhesive 2 can be cured by irradiating ionizing radiation such as ultraviolet rays or by thermosetting, and then the gasket 1 can be applied. It is also possible to apply the gasket 1 in an uncured state after applying the adhesive 2 and then cure the adhesive 2 of the gasket 1 at a time. The latter method in which the adhesive ability of the adhesive 2 can be maintained and the gasket 1 and the adhesive 2 are cured at a time is preferable in consideration of manufacturing efficiency.

  Although there is no restriction | limiting in particular about the thickness of an adhesive bond layer, 1/5 or less of the height of the gasket 1 is preferable. If the thickness of the adhesive layer becomes too thick, the compressive force becomes too high, and the sealing performance may deteriorate.

  The apparatus used for extruding the gasket 1 and applying the adhesive 2 is not particularly limited as long as it is an apparatus capable of forming the gasket 1 having a desired shape on the cover body 3, and is a pneumatic extrusion apparatus or a mechanical ram press. Examples thereof include an extrusion device and a plunger type extrusion device. The nozzle shape is not particularly limited, and examples thereof include a circular shape, an elliptical shape, and a polygonal shape. Moreover, although it can select suitably according to the width | variety of the gasket 1 about the internal diameter of a nozzle, it is the range of 0.1-1.2 mm normally.

  The extrusion pressure of the gasket 1 is appropriately selected depending on the type and viscosity of the gasket material, but is preferably 50 kPa to 1 MPa. Within this range, the gasket 1 can be pushed out efficiently, and the gasket 1 is not crushed, and the gasket 1 having a sufficiently narrow line width and high height can be obtained. From such a viewpoint, the extrusion pressure of the gasket 1 is more preferably in the range of 80 kPa to 800 kPa, still more preferably 100 kPa to 800 kPa, and even more preferably 200 kPa to 800 kPa.

  The molding temperature of the gasket 1 is appropriately selected depending on the gasket material used, but is preferably in the range of -20 ° C to 90 ° C, and more preferably in the range of 30 ° C to 70 ° C.

  The gasket 1 used in the present invention is not particularly limited as long as it contains a light transmissive resin as a main component. The light transmissive resin is not limited as long as it is a resin that transmits light and the color pigment of the adhesive 2 can be visually recognized from the gasket 1. However, urethane, epoxy polymer, silicone, polyisoprene, hydrogenated polyisoprene. Polybutadiene, hydrogenated polybutadiene, polyisobutylene, fluorine-containing rubber, and those obtained by modifying these are preferred, and ultraviolet curable resins are particularly preferred. These can be used alone or in combination of two or more.

  Moreover, as such a gasket 1, the thing which has acrylic modified urethane as a main component among these is the most preferable. Examples of the urethane modified with acrylic include urethane acrylate oligomer of polyether polyol, urethane acrylate oligomer of polyester polyol, or urethane acrylate oligomer having both ether group and ester group in the molecule and urethane acrylate of carbonate diol having carbonate group. An oligomer etc. can be mentioned.

  Examples of the polyether polyol include polyethylene glycol, polypropylene glycol, polytetramethylene glycol, polyhexamethylene glycol and 1,3-butylene glycol, 1,4-butylene glycol, 1,6-hexanediol, neopentyl glycol, and cyclohexane. A compound obtained by adding ethylene oxide or propylene oxide to dimethanol, 2,2-bis (4-hydroxycyclohexyl) propane, bisphenol A, or the like can be used.

  The polyester polyol can be obtained by reacting an alcohol component and an acid component. For example, polyethylene glycol, polypropylene glycol, polytetramethylene glycol and 1,3-butylene glycol, 1,4-butylene glycol, 1,6- Hexanediol, neopentyl glycol, 1,4-cyclohexanedimethanol, 2,2-bis (4-hydroxycyclohexyl) propane, bisphenol A, etc. added with ethylene oxide or propylene oxide, or ε-caprolactone added Can be used as the acid component, and dibasic acids such as adipic acid, sebacic acid, azelaic acid, and dodecanedicarboxylic acid, and anhydrides thereof can be used as the acid component. A compound obtained by reacting the above-mentioned alcohol component, acid component and ε-caprolactone at the same time can also be used as the polyester polyol.

  The carbonate diol is, for example, diaryl carbonate such as diphenyl carbonate, bis-chlorophenyl carbonate, dinaphthyl carbonate, phenyl-toluyl-carbonate, phenyl-chlorophenyl-carbonate, 2-tolyl-4-tolyl-carbonate, dimethyl carbonate, and diethyl carbonate. Carbonates or dialkyl carbonates and diols such as 1,6-hexanediol, neopentyl glycol, 1,4-butanediol, 1,8-octanediol, 1,4-cyclohexanedimethanol, 2-methylpropanediol, di Dipropylene such as propylene glycol, dibutylene glycol or the above diol compounds and oxalic acid, malonic acid, succinic acid, adipic acid, azelaic acid, hexahydrophthalic acid, etc. The reaction product of carbon acids, or can be obtained by transesterification of the polyester diol is the reaction product of ε- caprolactone. The carbonate diol thus obtained is a monocarbonate diol having one carbonate structure in the molecule or a polycarbonate diol having two or more carbonate structures in the molecule.

  In the gasket 1 used in the present invention, particularly preferable acrylic-modified urethane is a urethane acrylate oligomer of polyether polyol and polyester polyol, and the organic diisocyanate is not particularly limited, but methylene diisocyanate, tolylene diisocyanate. , Isophorone diisocyanate, 4,4'-dicyclohexylmethane diisocyanate and hexamethylene diisocyanate are particularly preferred.

  The gasket 1 used in the present invention preferably has a hardness of 50 degrees or less with a type A durometer based on JIS K6253. When the hardness is 50 degrees or less, the gasket 1 is easily deformed when the cover with gasket is incorporated into the main body, and the sealing performance is not impaired. From the above points, the hardness is preferably 45 degrees or less.

  In addition, the gasket 1 used in the present invention can be blended with an inorganic filler and / or an organic thickener to adjust the viscosity. As inorganic fillers, wet silica, dry silica or those were subjected to hydrophobic treatment with silane coupling agent, silicone oil, modified silicone oil, sodium fluoride, magnesium silicofluoride, nonionic surfactant, synthetic polyethylene wax, etc. , Bentonite, mica, synthetic smectite or those treated with a quaternary ammonium salt, and organic thickeners include hydrogenated castor oil, amide wax, polyethylene oxide and the like.

  Also, the gasket 1 used in the present invention includes clay, diatomaceous earth, talc, barium sulfate, calcium carbonate, magnesium carbonate, metal oxide, mica, graphite, aluminum hydroxide and other flaky inorganic additives, and various metals. Powder, glass powder, ceramic powder, granular or powdered or powdered solid filler such as polymer, other various natural or artificial short fibers, long fibers (eg glass fiber, metal fiber, various other Polymer fiber etc.) can be blended.

  Furthermore, weight reduction can be attained by mix | blending the hollow filler, for example, the organic hollow filler which consists of inorganic hollow fillers, such as a glass balloon, a polyvinylidene fluoride, a polyvinylidene fluoride copolymer. In addition, various foaming agents can be mixed in order to improve various physical properties such as weight reduction, and it is also possible to mix gas mechanically during mixing.

  In addition, the gasket 1 used in the present invention includes, as necessary, other flame retardants, antibacterial agents, hindered amine light stabilizers, ultraviolet absorbers, antioxidants, colorants, coumarone resins, coumarones. Adhesive elastomers such as indene resin, phenol terpene resin, petroleum-based hydrocarbons, rosin derivatives, etc. (tackfire), Rheostomer B (trade name: manufactured by Riken Vinyl Co., Ltd.), Hibler (trade name: Kuraray) Others such as a product made by the company, a block copolymer in which polystyrene blocks are connected to both ends of a vinyl-polyisoprene block), Norex (trade name: manufactured by Nippon Zeon Co., Ltd., obtained by ring-opening polymerization of norbornene) A thermoplastic elastomer or resin can be used in combination.

  Although it does not specifically limit about the viscosity of the gasket 1 used by this invention in the range which can apply | coat a gasket material, Usually, it is preferable that the viscosity in 50 degreeC is the range of 50-1000 Pa.s. When the viscosity at 50 ° C. is within this range, the fluidity is appropriate, so that the gasket shape can be maintained and the gasket shape can be easily shaped.

  In the manufacturing method of the gasket 4 for a hard disk device of the present invention, the adhesive 2 and the gasket 1 are sequentially applied and formed on the cover body 3, and then the gasket 1 and the adhesive 2 are simultaneously cured.

  In the method of manufacturing the gasket 4 for hard disk device, there are various curing methods. After the gasket 1 is molded, the active energy beam necessary for sufficiently curing the gasket 1 is irradiated from the active energy beam irradiation device and cured. The method is preferred. Here, the active energy rays used for curing the gasket 1 refer to ionizing radiation such as ultraviolet rays, electron beams, α rays, β rays, and γ rays. Among these, in particular, ultraviolet rays are easy to use and easy to use, and the gasket 1 can be cured well. Moreover, when using an ultraviolet-ray, it is preferable to make the gasket 1 contain a photoinitiator and / or a photosensitizer. In the case of using ionizing radiation such as an electron beam or α-ray, curing can proceed promptly without containing a photopolymerization initiator or a photosensitizer.

  As the photopolymerization initiator, known ones can be used and can be blended in the adhesive 2 and the gasket 1, but the photopolymerization initiator in the color pigment is light at a longer wavelength than the photopolymerization initiator in the gasket 1. An initiator that polymerizes is preferred. Moreover, when the phosphorescent pigment is blended in the color pigment, the excitation wavelength of the phosphorescent pigment is preferably excited at a longer wavelength than the photopolymerization initiator in the color pigment, and the difference is 20 nm. Further preferred.

  Examples of such photopolymerization initiators include intramolecular cleavage type photopolymerization initiators such as benzoin alkyl ethers such as benzoin ethyl ether, benzoin isobutyl ether, and benzoin isopropyl ether; 2,2-diethoxyacetophenone, 4 ′ -Acetone phenone type such as phenoxy-2, 2-dichloroacetophenone; 2-hydroxy-2-methylpropiophenone, 4'-isopropyl-2-hydroxy-2-methylpropiophenone, 4'-dodecyl-2-hydroxy Propiophenones such as 2-methylpropiophenone; Anthraquinones such as pendyl dimethyl ketal, 1-hydroxycyclohexyl phenyl ketone and 2-ethylanthraquinone, 2-chloroanthraquinone; Acylphosphine oxides; Benzophenone / amine as another hydrogen abstraction type photopolymerization initiator; Michler's ketone / benzophenone; thioxanthones; and amines based photopolymerization initiator and the like. In order to avoid migration of the unreacted polymerization initiator, a non-extraction type photopolymerization initiator can be used. For example, there are those obtained by polymerizing an acetophenone-based initiator and those obtained by adding a double bond of an acrylic group to benzophenone.

  These photoinitiators can also be used individually by 1 type or in combination of 2 or more types. When using a photoinitiator, the compounding quantity is preferably 0.5 to 5 parts by mass, more preferably 1 to 3 parts by mass per 100 parts by mass of the thermoplastic elastomer as the main component. Furthermore, in the gasket 1 used in the present invention, a photosensitizer, a thermal polymerization inhibitor, a curing accelerator, a pigment and the like can be blended within a range that does not impair the effects of the present invention.

  Examples of the ultraviolet light source include metal halide lamps, xenon lamps, low-pressure mercury lamps, high-pressure mercury lamps, and ultra-high pressure mercury lamps as electrode systems, and excimer lamps and metal halide lamps as electrodeless systems. The atmosphere for irradiating with ultraviolet rays is preferably an inert gas atmosphere such as nitrogen gas or carbon dioxide gas or an atmosphere with a reduced oxygen concentration. However, when the ultraviolet curable gasket 1 is used even in a normal air atmosphere, it is sufficiently cured. Can be made. The irradiation atmosphere temperature can usually be 10 to 250 ° C.

  Furthermore, the gasket 1 can be extruded from the extrusion port to the cover body, and at the same time, the gasket 1 can be cured by the ultraviolet rays irradiated from the ultraviolet irradiation device and integrated with the cover body 3. In this case, since the time from the extrusion to the curing is short, the extruded shape can be cured without being deformed.

  The cover body 3 integrated with the gasket 1 formed by extruding and curing the gasket 1 can be formed of a synthetic resin such as a metal or a thermoplastic resin. Examples of the metal forming the cover body 3 include nickel-plated aluminum, nickel-plated steel, cold-rolled steel, galvanized steel, aluminum / zinc alloy-plated steel, stainless steel, aluminum, aluminum alloy, magnesium, and magnesium alloy. Can be appropriately selected and used.

  Moreover, what injection-molded magnesium can also be used. From the viewpoint of corrosion resistance, a metal that has been subjected to electroless nickel plating is suitable. In the present invention, nickel-plated aluminum and nickel-plated steel are preferred.

  As an electroless nickel plating method, a known method conventionally applied to a metal material, for example, pH 4.0 to 5.0 containing nickel sulfate, sodium hypophosphite, lactic acid, propionic acid and the like in an appropriate ratio. For example, a method of immersing a metal plate in an electroless nickel plating bath made of an aqueous solution having a temperature of about 85 to 95 ° C. can be used.

  Examples of the thermoplastic resin forming the cover body 3 include styrene resins such as acrylonitrile styrene (AS) resin, acrylonitrile butadiene styrene (ABS) resin, polystyrene, and syndiotactic polystyrene, polyethylene, polypropylene, and ethylene-propylene copolymer. Olefin resins such as polypropylene composites, polyamide resins such as nylon, polyester resins such as polyethylene terephthalate and polybutylene terephthalate, modified polyphenylene ether, acrylic resins, polyacetal, polycarbonate, liquid crystal polymer, polyphenylene sulfide (PPS) And the like, and may be appropriately selected from these. The liquid crystal polymer is preferably a thermotropic liquid crystal polymer, and specific examples include polycarbonate liquid crystal polymers, polyurethane liquid crystal polymers, polyamide liquid crystal polymers, and polyester liquid crystal polymers. These resins may be used alone or in combination of two or more.

  In order to improve the adhesion between the cover body 3 and the gasket 1, the cover body 3 can be surface-treated in advance. Examples of the surface treatment include plasma treatment and corona discharge treatment. For the plasma treatment, a device such as a plasma irradiator manufactured by Keyence Corporation can be used.

  The inspection method for the hard disk device gasket 4 according to the present invention is an inspection method for confirming the application state of the adhesive 2 in the hard disk device gasket 4, and after the gasket 1 and the adhesive 2 are cured, from above the gasket 1. The application state of the adhesive 2 is visually confirmed. A specific visual recognition method is not particularly limited. For example, the hard disk device gasket 4 of the present invention in which a phosphorescent pigment and a fluorescent pigment are blended in the adhesive 2 is irradiated with black light in a dark place. Thus, the application state of the adhesive 2 can be visually recognized, and dot omission and fading can be easily determined. Further, by observing in a dark place, the influence of irregular reflection from the surrounding metal plate can be eliminated, and the visibility is further improved. Further, an image recognition device can be installed in a dark place to automatically inspect the application state of the adhesive 2.

Hereinafter, the present invention will be described in more detail with reference to examples. The present invention is not limited by this example.
Example 1
(1) Preparation of gasket material 400 g of a polyester diol compound (number average molecular weight 2000) obtained from 2,4-diethyl-1,5-pentanediol and phthalic anhydride, 82.4 g of norbornane diisocyanate, and antioxidant The agent, di-t-butyl-hydroxyphenol 0.10 g, was added to a 1 liter four-necked flask equipped with a stirrer, condenser, and thermometer, and reacted at 80 ° C. for 2 hours. Subsequently, 46.2 g of 2-hydroxyethyl acrylate, 0.10 g of p-methoxyphenol as a polymerization inhibitor, and 0.06 g of titanium tetra (2-ethyl-1-hexanolate) as an unreacted catalyst were added, and 6 at 85 ° C. Reacted for hours. A part of the reaction solution was taken out, and the end point of the reaction was confirmed by disappearance of the absorption peak of the isocyanate group at 2280 cm ^{−1 in} the infrared absorption spectrum, and the intended urethane oligomer was obtained. It was 18000 when the number average molecular weight was calculated | required by the polystyrene conversion value about the obtained urethane oligomer using the gel permeation chromatography. To 100 parts by mass of the urethane oligomer, 25 parts by mass of a monomer (phenoxyethyl acrylate) and 2 parts by mass of a polymerization initiator (4- (2-hydroxyethoxy) phenyl- (2-hydroxy-2-propyl) ketone) are blended. The resulting mixture was kneaded at 70 ° C. using a planetary mixer to obtain a gasket material.

(2) Preparation of adhesive (1) To 32 parts by mass of bisphenol A-based epoxy acrylate, 23 parts by mass of an acrylic monomer as a reactive diluent and 1 part by mass of IRGACURE 184 as a photopolymerization initiator are added, and talc as a filler. To 100 parts by mass as a whole. Next, 0.1 part by mass of a phosphorescent pigment was added to prepare an adhesive (1).

  The adhesive (1) was applied onto a nickel plated 0.4 mm thick aluminum plate of a 2.5 inch HDD using a three-dimensional automatic application control device to obtain an adhesive layer. As the three-dimensional automatic application control device, a dispenser machine was used as a pneumatic extrusion device, and a nozzle inner diameter of 0.72 mm was used.

(3) Manufacture of gasket The said gasket material was apply | coated on the adhesive bond layer using the same three-dimensional automatic application | coating control apparatus used by application | coating of an adhesive agent. Next, the gasket material and the adhesive were cured by irradiating with ultraviolet rays to form a gasket. As an ultraviolet irradiation device, “UV1501BA-LT” manufactured by Sen Engineering Co., Ltd. was used.

(4) Visual evaluation of gasket During the production of the gasket, an uncoated part of the adhesive was produced. The obtained gasket was visually evaluated to confirm application / non-application of the adhesive.

Example 2
An adhesive (2) was prepared in the same manner as in Example 1 except that the phosphorescent pigment in the adhesive (1) was changed to a fluorescent pigment. Next, a gasket was produced in the same manner as in Example 1 except that the adhesive (1) was changed to the adhesive (2), and the same evaluation was performed.

Comparative Example 1
An adhesive (3) was prepared in the same manner as in Example 1 except that the phosphorescent pigment in the adhesive (1) was not added. Next, a gasket was produced in the same manner as in Example 1 except that the adhesive (1) was changed to the adhesive (3), and the same evaluation was performed.

  In the gaskets obtained in Examples 1 and 2, the presence / absence of application of the adhesive and the fading of the adhesive (dot missing) can be visually confirmed, and the presence or absence of the adhesive and the fading of the adhesive (dot missing) are easily inspected. I was able to. On the other hand, in Comparative Example 1, the presence / absence of application of the adhesive and the blurring of the adhesive (dot missing) could not be visually confirmed, and the presence / absence of the application of the adhesive and the blurring of the adhesive (dot missing) could not be inspected.

It is a fragmentary sectional view showing a suitable example of a gasket of the present invention.

Explanation of symbols

1 Gasket 2 Adhesive 3 Cover 4 Gasket for hard disk device

Claims (5)

In the gasket for a hard disk device in which the gasket is bonded to the cover body via an adhesive,
The gasket for a hard disk device, wherein the gasket contains a light-transmitting resin as a main component, and the adhesive contains a color pigment.   The hard disk device gasket according to claim 1, wherein the colored pigment is a phosphorescent pigment.   3. The gasket for a hard disk device according to claim 1, wherein either one or both of the gasket and the adhesive mainly contains an ultraviolet curable resin. In manufacturing the gasket for a hard disk device according to any one of claims 1 to 3,
A method of manufacturing a gasket for a hard disk device, comprising: sequentially applying and forming the adhesive and the gasket on the cover body; and simultaneously curing the gasket and the adhesive. An inspection method for confirming the application state of the adhesive in the gasket for a hard disk device according to any one of claims 1 to 3,
A method of inspecting a gasket for a hard disk device, wherein the application state of the adhesive is visually recognized from above the gasket after the gasket and the adhesive are cured.

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